I have not seen velvet for so many years that I assumed it was erradicated, at least in this country.I imagined this was the result of the preventive tretments new stock was given by exporters as well as with local wholesalers.In the old days I used to quarantine and copper treat any new fish.But now,I´m embarrased to admit,I just drop any fish carelessly in my tanks. As deserved,I had a velvet outbreak in my main system .It was mild at first,and hard to ID.I first thought of Brooks,and lost some valuable time giving formalin baths.Then it began to spread,wiping tank fulls of clown juvis and killing adult fish in different tanks.I could only positiely ID the parasites when I checked a sick fish during a FW bath.Scores of round non motile 60-80 mics parasites dropped from the affected fish in short time.They swell in FW until they finally burst liberating lots of infecting tomonts.See the picture:

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At this time,I think I must stress the importance of the oodinum test,since velvet still shows and it is so deadly.Easy to perform,place the suspected fish in FW for some time and then check for dropped cysts at the bottom of the container.

So I decided to treat with copper.The 1st problem found was that my reagent read 0,no matter how strong the dose.Both it and my copper solutions were very old .So I made a fresh one and still got 0.I purchased some reagent of other brand and again negative .Then I saw it was also past expiration date.It seems nobody is using copper anymore around here,and LFS don´t carry them.At last I have one ordering one for me and this time it was some months before exp.date and working!.So I began by treating individual tanks where the disease was evident.I couldn´t medicate the system as I keep lots of invertebrates like ornamental shrimps and a considerable biomass of unwanted creatures:Aiptasias,nudibranchs,hydroids,fireworms and sponges.

Yes,but not without some collateral damage I started medicating individual tanks closing water circulation.Many sick fish died overnight,no matter they had an air stone.And new fish kept getting sick.So here was no short cut to treat the whole system.Though I am aware that copper is lethal to invertebrates,I had the stupid idea that crustacea were copper resistant.This comes from an old time experience when I nuked an empty tank with a copper overdose and found later some harp copepods still alive.Well, shrimps and copper don´t mix .They began to die and I decided to move them to a clean system,giving them a short FW bath just to be sure they were not carrying the disease.In no time all of them were dead.So now I have learned 3 lessons:

When faced to some unclear disease,perform the FW test and check for oodinum.Copper kills all inverts,including shrimps.FW exposure kills shrimps.The 4th lesson,which I already knew but tried to play different,is that the whole system must be medicated and levels of Cu must be maintained for at least 10 days.

Then it was a matter of cleaning tons of dead sponges and firworms.Luckily those worms living in the DSBs came to the surface to die and those dwelling in the drain pipe system were washed into the filter floss.The only positive result of this ordeal is that hydroids were also gone,after been pested by them for so many years!

The treatment was effective and the disease was erradicated from the system.But I am now suffering a post treatment effect on fish reproductive performance.All the fish in the system (clowns,dotties,damsels)stopped spawning.After some time,they are slowly reassuming spawning,but alas,all spawns vanish in 1-2 days,presumely infertile.Hopefully this problem will be reverted in the future I had a couple of cherubfish,C.argus,that died at the onset of treatment.The fish were sick and I thought the cure arrived too late.But no,it seems that Centropyge are especially sensitive to copper treatment.So two more lessons to aknowledge

Several months have elapsed and the clown/damsel factory remains closed All clown pairs are now spawning regularly nice large nests,but they don´t develop.They vanish the following day in the case of ocellaris/percula and their hybrids.Maroon and tomatos last 2-3 days.Since the eggs look so nice,I assumed copper has affected male fertility,perhaps definitely since the condition has not improved after several months. Lately,I lost my Premnas male which was replaced with a new one.Soon they were spawning,but the eggs keep dissapearing as usual.Intriguing and frustrating...

After 4 months,I still didn´t get any clown hatched,but things are slowly improving Now some spawns are fertile,and eggs are dissapearing partially,with some remaining close to hatching time.Again,tomatos are doing better than ocellaris/percula/maroons.

And last night,the first nest hatched (ocellaris) 6 1/2 months post copper.Nice complete hatch in the 8th night.Only to find all larvae dead next morning .A typical MPD case (massive perinatal death)aka 1st night death.Interesting though.MPD,total or partial has pested some clown breeders for years and several theories attempted to explain it,but we remain mostly clueless.Now there is a linear toxic effect on clown reproduction:no spawning>infertile eggs vanishing soon>some eggs developing for some time>eggs developing normally and hatching but lost to MPD.During these months,system water had regular changes,plus carbon,skimming and UV.

Endly,newly hatched larvae survive 1st night and I can resume breeding clowns| And Chrysiptera hybrids started to spawn again.Which marks the end of my 7 mo.trip thru the effects of copper on fish reproduction.Luckily,no permanent damage was done.